The invention relates to a device and a method for cooling an electricity storage means, such as a battery. It also relates to a vehicle, such as a car, comprising such a device, which comprises an electric power train.
The power train unit is fed by an electricity storage means with high energy potential which may take on the form of a so-called high voltage battery, or else a fuel battery. To preserve the lifespan of the electricity storage means, the electricity storage means must be cooled to maintain it within a temperature range acceptable for the components it contains.
When the vehicle is in operation, a portion of the electric power delivered by the storage means is used for its own cooling, which can be achieved through various methods such as circulation of a heat transfer fluid in a cooling circuit or by circulating an air flow using a fan. An implementation problem resides in attempting this cooling when the vehicle has stopped, and more specifically, when the power train unit has been under great stress during the moments preceding stoppage of the vehicle and when the power storage means has reached a high temperature. But, for safety reasons, the high energy potential means cannot continue to draw power to ensure its cooling when the vehicle is at a standstill.
The power storage means with high energy potential is said to be in operation when it delivers electric power to a circuit that is necessarily closed. It is no longer in operation when the electric circuit of which it is a part, is open.